basefindx(expression,sentence,dataset,ruleset) → expression / false
The basefindx subroutine takes as arguments an expression (called the aspect), a sentence (called the query), a dataset, and a ruleset. It uses the facts in the dataset and the rules in the ruleset (and only those facts and rules) to derive an instance of the query. If it succeeds, it returns the corresponding instance of the aspect; if it fails to derive an instance of the query, it returns false.
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Call: definefacts(repository,readdata('p(art,bob) p(bob,cal) p(bob,cam)'))
Exit: true
Call: definerules(library,readdata('g(X,Z) :- p(X,Y) & p(Y,Z)'))
Exit: true
Call: basefindx('Z',read('g(art,Z)'),repository,library)
Exit: cal
Call: basefindx('X',read('g(art,cal)'),repository,library)
Exit: art
Call: grind(basefindx(read('answer(X,Z)'),read('g(X,Z)'),repository,library))
Exit: answer(art,cal)
Call: grind(basefindx(read('answer(X,Z)'),read('p(X,Y) & p(Y,Z)'),repository,library))
Exit: answer(art,cal)
Call: basefindx('Z',read('g(bob,Z)'),repository,library)
Exit: false
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The basefindx subroutine differs from compfindx in that it does not use the definitions of predefined functions and relations (except for same and distinct. Otherwise, they are equivalent.
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